Научная статья на тему 'Male-mediated gene flow in the toad-headed lizards Phrynocephalus przewalskii'

Male-mediated gene flow in the toad-headed lizards Phrynocephalus przewalskii Текст научной статьи по специальности «Биологические науки»

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Ключевые слова
MALE-MEDIATED GENE FLOW / MICROSATELLITE DNA / MTDNA / PHRYNOCEPHALUS / POPULATION GENETIC STRUCTURE / VICARIANCE

Аннотация научной статьи по биологическим наукам, автор научной работы — Fu Jinzhong

Using mitochondrial and microsatellite DNA data and a population genetic approach, we tested male-mediated gene flow in the toad-headed lizards Phrynocephalus przewalskii. The mitochondrial DNA (ND2 gene), on the one hand, revealed two major lineages and a strong population genetic structure (FST = 0.692; FST0 = 0.995). The pairwise differences between the two lineages ranged from 2.1% to 6.4% and the geographic division of the two lineages coincided with a mountain chain consisting of the Helan and Yin Mountains, suggesting a historical vicariant pattern. On the other hand, the nuclear microsatellite DNA revealed a significant but small population genetic structure (Fst = 0.017; Fst1 = 0.372). The pairwise Fst among the nine populations examined with seven microsatellite DNA loci ranged from 0.0062 to 0.0266; the assignment test failed to detect any naturally occurring population clusters. Furthermore, the populations demonstrated a weak isolation by distance and a northeast to southwest clinal variation, rather than a vicariant pattern. Morphological examination also corroborated the nuclear gene pattern. A historical vicariant event followed by male-mediated gene flow appears to be the best explanation for the observation. Approximately 2 5 Ma, climatic change may have created an uninhabitable zone along the Helan-Yin mountain chain and initiated the divergence between the two mitochondrial lineages. With further climatic changes, males were able to disperse across the mountain chain, causing sufficient gene flow that eventually erased the vicariant pattern and drastically reduced the population genetic structure, while females remained philopatric and maintained the mitochondrial DNA divergence. Although polygyny mating system and female philopatry may partially contribute to the reduced movement of females, other hypotheses, such as female intrasexual aggression, should also be explored.

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Текст научной работы на тему «Male-mediated gene flow in the toad-headed lizards Phrynocephalus przewalskii»

DeAgamis2: ВТОРОЙ МЕЖДУНАРОДНЫЙ СИМПОЗИУМ ПО АГАМОВЫМ ЯЩЕРИЦАМ

MALE-MEDIATED GENE FLOW IN THE TOAD-HEADED LIZARDS PHRYNOCEPHALUS PRZEWALSKII

Jinzhong Fu

Department of Integrative Biology, University of Guelph Guelph, Ontario N1G 2W1, Canada E-mail: [email protected]

Using mitochondrial and microsatellite DNA data and a population genetic approach, we tested male-mediated gene flow in the toad-headed lizards Phrynocephalus przewalskii. The mitochondrial DNA (ND2 gene), on the one hand, revealed two major lineages and a strong population genetic structure (FST = 0.692; FST0 = 0.995). The pair-wise differences between the two lineages ranged from 2.1% to 6.4% and the geographic division of the two lineages coincided with a mountain chain consisting of the Helan and Yin Mountains, suggesting a historical vicariant pattern. On the other hand, the nuclear microsatellite DNA revealed a significant but small population genetic structure (Fst = 0.017; Fstl = 0.372). The pairwise Fst among the nine populations examined with seven microsatellite DNA loci ranged from 0.0062 to 0.0266; the assignment test failed to detect any naturally occurring population clusters. Furthermore, the populations demonstrated a weak isolation by distance and a northeast to southwest clinal variation, rather than a

vicariant pattern. Morphological examination also corroborated the nuclear gene pattern. A historical vicariant event followed by male-mediated gene flow appears to be the best explanation for the observation. Approximately 2 - 5 Ma, climatic change may have created an uninhabitable zone along the Helan-Yin mountain chain and initiated the divergence between the two mitochondrial lineages. With further climatic changes, males were able to disperse across the mountain chain, causing sufficient gene flow that eventually erased the vicariant pattern and drastically reduced the population genetic structure, while females remained philopatric and maintained the mitochondrial DNA divergence. Although polygyny mating system and female philo-patry may partially contribute to the reduced movement of females, other hypotheses, such as female intrasexual aggression, should also be explored.

Key words: male-mediated gene flow, microsatellite DNA, mtDNA, Phrynocephalus, population genetic structure, vicariance.

ASEXUALITY ON THE BEACH: PHYLOGENY, BIOGEOGRAPHY AND THE ORIGIN OF PARTHENOGENESIS IN LEIOLEPIS

Jesse L. Grismer, Todd Jackman, Aaron M. Bauer, L. Lee Grismer, Kumthorn Thirakhupt, Anchalee Aowphol, Chan Kin Onn, and Perry L. Wood Jr.

Department of Biology, Villanova University 800 Lancaster Ave, Villanova, PA, 19085, USA E-mail: [email protected]

The Southeast Asian agamid lizard genus Leiolepis Cuvier, (1829) is an enigmatic, lineage, differing form other lizard groups in general morphology and ecology. Currently, Leiolepis contains nine species that collectively range throughout Indochina and the Malay Peninsula. Of these nine species, four are all female, parthenogenic species. Unlike their sexual congeners, these asexual species

have pocketed distributions throughout Southeast Asia and are only found in secondary, or perpetually disturbed habitat. Using the mtDNA gene ND2, and two rapidly evolving nuclear genes we investigated the origins of these asexual species, and present a species level phylogeny for Leiolepis.

Key words: phylogeny, biogeography, aga-mid lizards, Leiolepis, parthenogenesis.

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СОВРЕМЕННАЯ ГЕРПЕТОЛОГИЯ 2010 Т. 10, вып. 3/4

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